Submersible pump



Dec. 31, 1963 H. J. FELTUS SUBMERSIBLE PUMP 2 Sheets-Sheet 1 FiledJuly25. 1961 l N VEN TOR. Hf/Vk Y JAMES FL TUS ATTORNEYS Dec. 31, 1963 H. J.FELTUS 3,115,840

SUBMERSIBLE PUMP Filed July 25. 1961 2 Sheets-Sheet 2' INVENTOR.

HENRY JAMES FELTUS AT ORA/F Y5 United States Patent 3,115,840SUBMERSEBLE FUR/ll Henry James Feltus, Seneca Falls, N.Y., assignor toGoultls Pumps Incorporated, Seneca Falls, N.Y. Filed July 25, 1961, Ser.No. 126,621 2 Claims. (Cl. 193-87) This invention relates to submersiblepump assemblies and pertains more particularly to certain novelcombinatlonal aspects in conjunction with submersible pumps of the deepwell type.

In relation to deep well pumps as contemplated within the scope of thepresent invention, reference is had to operations in conjunction withwells extending in depth from in the neighborhood of 1500 feet to andbeyond 10,0(ld feet. At the present time, the more conventional type ofdeep well pump, i.e., sucker rod type and others, are more increasinglybeing replaced by centrifugal pumps of the single or multistage typehaving, in association therewith, electric motors which may be eitherpositioned above or below the pump but in close proximity thereto andwhich are kept dry by sealed housings filled with oil or wherein thesealed windings of the motors are insulated by being potted in plasticresin material. Pumpmotor systems of this type are normally built in onelong casing and are adapted for a particular capacity suitable forpumping purposes within a discrete range of conditrons. Such a pumpassembly, if it is to be of considerable capacity and suitable foroperations at extremely great depths, is of necessity a structure havingconsiderable length and is characterized by its fragility andunwieldiness rendering the same particularly difficult to transport.Also, such assemblies are normally of such construction as not to lendthemselves readily to repair except by such equipment as themanufacturer alone possesses. It is consequently of primary importancein connection with the present invention to provide a standard modularpump unit having a specific capacity and to utilize in associationtherewith, a motor unit of modular form matching the capacity of thepump and capable of operation in conjunction therewith to provide therequisite power, the modular units permitting of cumulativeinterconnection and operation so as to accommodate for widely varyingpower requirements.

A further concern in connection with the present invention is to providea modular assembly substantially as is described above wherein anyrequired number of motor units can be connected together and wherein therequisite number of pump units can be readily attached thereto, one tothe other, so that the over-all effect is a balanced and matchedmotor-pump assembly capable of operation under any given set ofconditions and performing the desired work in an efficient manner.

A further object of the present invention resides in the provision ofmodular type pump and motor units capable of cooperation with each otherin various combinations wherein the pump unit is characterized by itsnovelty of construction wherein the same may be readily disassembled andreassembled in the field without the necessity for special tools andequipment therefor. More spe cifically, an object of the presentinvention is to provide a modular type of pump assembly wherein the sameis provided with an outer housing or casing of tubular form which isrequired only to sustain assembly forces and is not required to besubjected to the internal pressure of the pump system. Ancillary to thisrelationship, a modular pump unit so constructed is characterized by itsease of assembly and disassembly, even in the field and under conditionsrequiring only such equipment as would normally be available in thefield.

More specifically, the above objects are accomplished by a specificconstruction of pump units wherein the same dilidh Patented Dec. 31,1963 is characterized by having a bowl portion which forms the actualhousing or casing for the pump assembly to confine the liquid beingpumped therewithin, such bowl in each instance being housed within anouter tubular casing in loosely fitted relationship therewithinso as tobe easily removed and replaced relative thereto.

A further object of this invention resides in the novel cooperation ofthe component parts of individual pump units in connection with thepresent invention wherein the pump units in each case are of thecentrifugal type embodying a bowl which houses a diffuser means and animpeller means wherein the bowls of the pump units are manufacturedwithin tolerances providing spaced upper and lower locating surfacesthereon, which when such units are disposed in stacked relationship,they will bear specific positional relationship with each other. Inconjunction with this relationship, the axial length of the hub of theimpeller means of each unit is held within a tolerance whose upper limitis equal to or at least does not exceed the lower limit of the tolerancefor the spacing between the locating surfaces of the bowls. In thisfashion, the upper locating surface of each bowl is easily usable as agauge surface for a straight edge device to determine the properposition of the impellers as the same are assembled. This is achieved byvirtue of the fact that by maintaining the conditions as specified, theupper hub sunface of an impeller means Will always be below, or ideallywill be at the same level as the upper locating surface of the bowlwithin which it is assembled. In those cases where the hub surface isbelow the locating surface, shim means is employed to equalize thelevels.

A further object of the present invention resides in the provision of amodular type of pump assembly Wherein the modular units are adapted tobe detachably connected to each other in end to end relationship and tobe associated with modular power means wherein slight modularmisalignment is compensated for in the pump modules by the use of novelcombination in the means for driving the pump units. In this connection,the present invention envisages a modular pump unit having its owndriven shaft adapted to be coupled to extensions thereof at either endand wherein the means for supporting the drive shaft embodies rigid mainlocating bearing means located a substantial distance from the endsthereof so that shafts may accommodate for slight misalignment as mayoccur during the assemblage of adjacent modular units one to the otherwithout materially detracting from the eificiency of the device.

The foregoing and other objects, advantages and characterizing featuresof the present invention will become clearly apparent from the ensuingdetailed description of one, illustrative embodiment thereof, taken inconjunction with the accompanying drawings illustrating the same whereinlike reference numerals denote like parts in each view, and wherein:

FIG. 1 is a sectional view taken through a portion of a well showing acombined motor-pump assembly installed therein;

FIG. 2 is an enlarged elevational view partly in section illustratingdetails of the internal construction of one of the modular pump unitsand the manner of interconnection between adjacent units;

FIG. 3 is an enlarged elevational view partly in section showing themanner in which one of the modular pump units is connected to a portionof the driving mechanism therefor;

FIG. 4 is a horizontal section taken substantially along the plane ofsection line 4-4 in FIG. 3 showing details of one of the pump units;

FIG. 5 is a sectional view taken substantially along the plane ofsection line 55 in FIG. 3 illustrating further details of one of thepump units;

FIG. 6 is a sectional view taken substantially along the plane ofsection line s s in FIG. 3 illustrating certain details of themechanism;

FIG. 7 is an elevational view partly broken away to illustrate themanner in which dummy units may be places within the confines of asingle modular pump unit; and

FIG. 8 is an enlarged sectional view showing a break away plug utilizedin association with the assemblage as illustrated.

Referring at this time more particularly to FIG. 1, a section of a wellis shown therein and more particularly the bottom portion is shownspecifically in this figure. Reference characters 1%, l2. and 1indicates in general submersible motor units coupled together in end toend relationship as shown and being provided with a heat exchanger unitto of conventional nature. Coupled to the heat exchanger unit 16 is afirst modular pump unit 18 and then successively coupled thereto is themodular pump unit 26* and finally the upper modular pump unit 22. Inaccord with prevailing practice, the entire assemblage as abovedescribed would be housed within a single integral unit and, moreover,it is also conventional to so construct the pump portion of such a unitso that the same is not easily disassembled except by special tools andequipment such as would normally be possessed only by the manufacturerof the pump unit and would not usually be available for field usage. Thegreater the depth of the well and the greater the capacity desired ofthe pump and motor assembly, the greater will be the over-all length ofthe assemblage. 'The motor units 1%, 12 and 14 per se form no part ofthe present invention. They constitute, with the heat exchanger 16, asealed modular unit in and of itself, including the various couplingmembers 24, 26 and 23. According to the present invention, the pumpunits such as 18, 2t} and 22 are not only separate from each other, eachbeing of modular form, but are also separate from each motor-heatexchanger module comprising members 10, 12, 14 and 16 which may be used.It will be understood that any number of motor-heat exchanger modulesmay be used and that, correspondingly, any requisite number of pumpmodules may be used therewith, as may be required to meet the demands ofthe particular situation involved. Such a relationship is in contrast toprevailing practice wherein a single, integrated unit, specificallyconstructed to apply to a particular problem, is used. Such prevailingunits present difliculty in shipment due to their considerable lengthand their susceptibility, by virtue of such length, of damage duringtransit.

Referring now more particularly to FIG. 3, the connection between theheat exchanger unit 16 and the next uppermost pump unt i8 is shown. Thisis accomplished by means of an adapter indicated generally by thereference character 3%} which includes an upstanding body portion 32pgovided with a flange 34 at its lower end suitably apertured incircumfere-ntially spaced relationship therearound to receive aplurality of fasteners 36 by means of which the adapter is detachablysecured to the heat exchanger unit 16. An intermediate portion of thebody 32. is provided with a series of circumferentially spaced fluidinlet openings 38 and a suitable screen at? encompasses these openingsas is shown to protect the same from clogging by foreign material whichmay be present in the liquid being pumped.

The drive shaft means operated by the motors l d, 12 and 14 proiectsupwardly from the heat exchanger unit 16 and terminates in a splined orotherwise feathered shaft portion 42 for cooperation with a couplingsleeve id substantially as is shown. The coupling sleeve is internallygrooved as at 46 to receive a suitable seal 4-3 embracing the driveshaft extension and the upper end of the sleeve 44 is provided with aninternally hexagonal sleeve t? rigid therewith, although it is to beunderstood that the hexagonal portion provided by the sleeve 4 5 may beintegrally formed from the sleeve 4 i itself. Preferably, however,sleeve 5th is externally splined to be nonrotatably received by sleeve44.

The sleeve 44 projects upwardly within the body 32 of the adapter 39within the confines of the hub portion 52 thereof, such hub terminatingat its upper end in an inturned flange portion 5 2 for the purpose ofretaining a resilient bushing member 5a. The drive shaft for the pumpunit 13 is indicated by the reference character 58 and is of noncircularcross section, specifically being of the hexagonal form as shown in thedrawings. Resting upon the upper end of the sleeve 44 is a bearingsleeve of} having a hexagonal bore therethrough receiving the shaft 5%,the sleeve being journalled within the resilient bushing 56 to receive alimited degree of bearing support therefrom. interposed between theshafts 42 and 58 is a thrust button 62 which will be noted to underliethe lower end of the insert sleeve Sil previously described, the purposeof this construction being presently apparent.

The upper end of the adapter 3%) is provided with external buttressthreads as is indicated by reference character 64 and terminates in anupstanding flange 65 extending circumferentially therearound andprovided with its upper surface parallel to the lower surface of thebody of the adapter 38. Such upper surface of the flange 65 presents agauging surface 92 as will be more particularly pointed out hereinafter.

. Referring at this time more particularly to FIG. 2, it will be seenthat the assemblage 1 8 hereinabove described consists essentially ofthe aforementioned adapter 30, a tubular housing or casing 66 and anupper plug or adapter as, all cooperative together to sandwich betweenthe two adapters 3d and 68 a plurality of stacked pump units such asthose indicated by reference character 7% At intermediate points withinthe casing 6-6 and spaced a substantial distance from the adapters 3dand 63 are bearing spider assemblies indicated generally by referencecharacters 72 and '74 for the purpose of locating the drive shaft 53 forthe pump unit 18 as will be hereinafter more particularly pointed out.

The upper adapter 68 is screwthreaded into engagement with the casing 18as is the lower adapter 3t) and each are preferably provided withbuttress type threads since these two adapters are responsible for theforcible sandwiching of the pump units therebetween and serving tomaintain the same in aligned relationship.

Referring again to FIG. 3, it will be seen that each pump unit includesa bowl 849 having an upstanding cylindrical side wall whose outerdimension is slightly less than the inside dimension of the casing 66 soas to provide clearance therebetween substantially as is shown, thepurpose of which will be presently explained. Each bowl also includes abottom wall 82 having a central opening 84 for inducting the liquidbeing pumped therethrough into the eye of the impeller unit indicatedgenerally by the reference character 86. Each bowl (iii is provided withtwo locating surfaces thereon, one, the lower, being formed by the undersurface 88 of the downwardly projecting shoulder portion 136 thereof andthe other, or upper, formed by the surface 89 surrounding the upperflange portion 90 thereof. The lowermost pump bowl 8%) rests upon theupper locating surface surrounding the flange 65 of the adapter 3t sothat hearing contact is provided between the upper locating surface ofthe adapter 3% and the lower locating surface 88 of the bowl 86.Likewise, the next pump unit 94 has its lower locating surface bearingagainst the upper locating surface 89 of the lower bowl 843. By holdingthe distance between the lower locating surfaces of each bowl unitwithin prescribed tolerances, efiiciency and accuracy in assembling theunits is permitted, as will be hereinafter more particularly explained.

Also fitted within each bowl 8% is a diffuser assembly including a lowerportion 1% and an upper cover Till, the latter of which just clears theunder surface of the bowl unit immediately thereabove and the former ofwhich is bottomed within its associated bowl. The particularconstruction of the impeller 86 is shown more clearly in FIG. 5 of thedrawings wherein it will be seen that the same is provided with ahexagonal hub sleeve 102 which drivingly engages the drive shaft 58 forthe pump unit, the sleeve 102 being received in the hub portion 164 ofthe impeller. Extending spirally from the hub 104 are a series ofimpeller vanes 106 which term-inate at the peripheral edge of theimpeller, substantially as is shown. The lower portion 1% of thediffuser assembly presents a series of stationary vanes 1% formingpassages 119 therebetween which mate with notches 112, see particularlyFIG. 4, on the periphery of the cover member d. The under surface of thecover 161 is provided with a circumferentially extending shoulder ofuniform inside diameter as indicated by the dotted line 114 in FIG. 4and provided with spiral steps on its outer surface as indicated by thedotted line 116 in FIG. 4. The forward edges of such steps, which arecoextensive with the corresponding radial edges of the notches 112, forma male element cooperable with the trailing edges 118 of the fixedspiral vanes 10 8 of the lower diffuser member 161?, see particularlyFIG. 5, serving to locate the upper and lower members relative to eachother and properly positioning the same so that the notches 112 areproperly oriented with relation to the channels 116. Further to thisend, it will be noted that the outer surface of the lower portion 166 ofthe diffuser assembly is recessed in its outer surface as at 129, seeparticularly FIG. 3, starting from the forward edge 122 (see FIG. 5) ofeach of the stationary vanes 168 and being substantially coextensivewith the notches 12.. In this fashion, the liquid flow is as indicatedby the arrows in FIG. 3. The upper surface of the member 162 is providedwith a series of stationary spiral vanes 124 for guiding the liquidtoward the eye of the next uppermost impeller unit.

In assembling the unit 13 above described, it will be appreciated thatthe units 16, 12, 1-4 and 16 are first interconnected or assembled andsuitably supported to be lowered into the well. Next, the adapter Stl ispositioned and secured to the member 16 and the sleeve 44 is engaged onthe shaft 42 whereafter the sleeve 66 and shaft 58 are fitted in place.The naked upstanding shaft 58 provides a guide and retaining means forthe series of impellers 86 which are to be stacked therupon in hearingengagement with the upper end of the sleeve 6% and the locating surface86 of the adapter Ell provides a base upon which the bowl units 8t) arestacked. The downwardly projecting shoulder portions 130 whichcircumscribe the flanges 62 or 90, as the case may be, hold 0- ring sealmembers 132 captive therebetween. The first sequence for assemblingconsists of placing a seal 132 and a bowl 86 on the locating surface ofthe adapter 36 which operation more or less centers the bowl. Then, thelower member 1W of the diffuser is positioned as is the impeller means$6. And lastly, the cover member 1611 is positioned to complete thefirst pump unit. However, before placing this first pump unit, ameasurement is first made with a straight edge lying on the uppergauging surface 92 of the adapter to see What positional relationshipthe upper end of the bearing sleeve 60 has relative to such gaugingsurface 9 2. Manufacturing tolerances are maintained such that normallythis member will either be substantially at the same level as thegauging surface or somewhat therebelow. In the instance that the upperend surface of the bearing sleeve 6% is below the gauging surface 92 ofthe adapter 3%, suitable shims are placed on top of the sleeve 69 tobring the level to that of the gauging surface at the upper end of theadapter 36. Then, when the impeller '86 is positioned within the bowl80, the lower edge of the same will be coplanar with the gauging surface92. This, in turn, will position the upper edge of the impeller hubsubstantially level with the gauging surface 96 of bowl 86*. Finalleveling is accomplished by shim members.

The above operations are repeated until all of the pump units have beenpositioned in vertically stacked relationship. In respect to this, itwill be noted that by holding the vertical spacing between the lowerlocating surface 83 and the upper locating surface 89 of each pump bowlwithin tolerances whose lower limit is always at least as much as orgreater than the upper limit of the tolerance in which the axial lengthof the impeller hub is held while also accurately locating each gaugingsurface so that the vertical spacing between any adjacent two is notless than the spacing between locating surfaces, by pursuing the abovementioned assembly steps, the condition will always prevail whereineither the impeller hub is located properly with respect to the gaugingsurface of its associated bowl or it will require a minimum of shimmeans to bring the same up to that level. Thus, when the last pump unithas been installed, it is readily assured throughout the entireassemblage that the impellers are all properly related with respect totheir diffuser means in their individual pump units.

As was mentioned previously, the casing or housing 66 of each modularpump unit sustains only assembly forces and is isolated from pumppressure. This is due to the presence of the seal members 132 whicheffectively confine the liquid pressure within the bowls. Also, it willbe appreciated that by properly dimensioning the outside of the bowls,the same can be made to freely fit within a standard tubular casing 66so as to minimize the cost of construction.

After all of the pump units have been stacked as preiously described,the casing 66 is lowered thereover and threadedly engaged with theadapter 36. At this time, the adapter 63 may be already positioned onthe upper end of the casing 66 or it may be later applied. In eithercase, the next step is to thread the adapters 3t) and 68 tightly withinthe opposite ends of the casing 66 so that the pump bowls are subjectedto a compressive force sustained by tension in the casing or housing 66.As a means of a lock to hold the position between the various adaptersin the casings, the fasteners 134, see particularly FIG. 6, which holdthe retaining shield 136 for the power conductors 138 may be sopositioned as is shown in FIG. 6 to retain the adapter and casing inlocked relationship.

It will be noted that the upper adapter 68 previously described containsno bearing provision but the next adapter which is directly attachedthereto and indicated by the reference character 146 in FIG. 2 containsa hearing M2 rigidly attached thereto as by radial webs 144- or othersuitable means as may be desired. The adapter 146 for the uppermost unit22, on the other hand, varies somewhat in construction of the previouslymentioned adapters in that it is provided with a cap like bearingretainer guidably receiving the upper end of its associated drive shaft150. This adapter 146 is provided with an opening receiving a checkvalve element indicated generally by the reference character 152 whichis of entirely conventional nature and forms no part of this invention.The adapter 146, in turn, receives a replaceable adapter unit 154 whichincludes the break-away plug element 156, the adapter 154 being securedto the lower end 158 of the pipe through which the fluid is transmitted.

FIG. 8 serves to illustrate the purpose of the adapter 15 which housesthe rcak-away plug element 156. The plug element 156 is entirelyconventional in nature and, as is shown in FIG. 8, its purpose is to bebroken away to permit fluid to drain out of the tubing 158 when theentire assemblage is raised for any reason whatsoever. In order toachieve this, as is well known in the art, a suitable object is loweredthrough the pipe 158 and caused to strike the plug 156 and break thesame oif as is illustrated in dotted lines in FIG. 8.

From the above, it will be apparent that the weight of the bowls and thediffuser means is carried by the stationary portions of the devicewhereas the weight of the drive shafts is not imparted to the impellerssince the drive shafts are freely slidable therewithin. At the sametime, the rotating shaft assemblage also carries the weight of theimpellers by virtue of the stacked relationship of these members. Forexample, all of the impellers of section 18 are carried by bearingsleeve 6% as is the weight of all of the other impellers of the units 29and 22, although in the case of the unit 13, the load is imparteddirectly from the impellers, in stacked relationship, to the sleeve 6t).In the case of the next uppermost unit Zll, it will be noted that thecoupling sleeve 16% thereof is provided with an integral thrust button162 which engages on the upper end of the shaft 58 and permits the shaft164 to bottom thereon. This bearing sleeve 166 forms a seat for all ofthe impellers thereabove within the unit 20 and thus their weight istransmitted through the sleeve 160 to the shaft 58. This relationship issimilar for all instances at the couplings. For example, the dead weightof as many drive shafts as are involved is transferred to shaft 42 asindicated by arrows 167 hi FIG. 3. The weight of all the impellers, onthe other hand, as indicated by arrows 169 in this figure, aretransferred to shaft 42 through member 44 as indicated by the arrows at171.

The construction as thus far described is easily assembled ordisassembled in the field since the physical disengagement betweencomponent parts is readily effected by conventional tools and since thepositioning of the pump unit as aforesaid is a simple matter in view ofthe particular manner of construction as is described. Any straight edgecan be used for gauging purposes to determine the proper level for theimpeller hubs and, needless to say, the process of positioning the lowerend of each impeller hub substantially coplanar with the under surfaceor lower locating surface of its associated bowl assures properpositioning of that impeller within its associated diffuser means andbowl assembly.

At the same time, it will be readily appreciated that the bearingspiders 72 and 74 previously described are associated in each of thepump units but in such positions spaced relatively from their associatedplugs or adapters at the opposite ends of the casing within which theyare associated so that slight misalignment between units can occurwithout unduly binding the drive shaft associated with that particularunit or any of the other units. That is to say, considering FIG. 2,assume a slight misalignment between the two components 16 and 18. Sincethe lowermost bearing is of a resilient type, such misalignment iseasily accommodated for and the deflection of the shaft will bedistributed over a relatively large percent of the length of the shaft53, that is up to the first bearing spider assembly 72, therebypreventing any highly localized pressure on the bearing assembly 72 aswill tend to bind the shaft 53 and cause ultimate destruction of thebearing supporting means therefor. In the specific embodiment shown inFIG. 2, the upper end of the shaft 58 is devoid of any kind of supportand is free to flex at any point above the bearing spiders 7d. The loweradapter 140 for the next uppermost unit is provided with the hearingmeans 142 which therefore serves as the locating means for the lower endof shaft 164 and thus also for the upper end portion of shaft 58 bymeans of sleeve loll. This relationship is used throughout for allintermediate units. That is, for all intermediate units, there is norigid bearing support for its shaft immediately adjacent the upper endthereof whereas such a bearing is provided at the lower end so that, forany two adjacent units, of the two shafts which are coupled, only one isrigidly supported adjacent the juncture between the two units.

Also in conjunction with the ease of disassembly and assembly of thedevice in the field, .it will be readily appreciated that dummy meansmay be provided in any given pump unit so as to reduce the capacitythereof as may be required under certain circumstances to more evenlybalance the power requirement of the pump units used under any given setof circumstances in conjunction with the number of motor units employed.That is to say,

under some circumstances, it may be desired to used say only a half ofthe pump unit in association with one motor unit. In this instance, thepump unit can be assembled so that only half of the pump assembliesthereof are operative. The fashion in which this may be achieved isclearly illustrated in FIG. 7 of the drawings wherein it will be seenthat two adjacent bearing spider assemblies 17% and 172 are employed tocut down the over-all capacity of the pump. This figure also illustratesfurther bearing spider assemblies 174- and 176 to further out down thecapacity of the pump unit shown. Needless to say, it is not necessary toemploy only bearing spider units to cut down the pump capacity, sinceother means may be employed. For example, dummy pump bowls may beutilized which contain only an axial sleeve space corresponding inlength to the length of an impeller hub or various other means may beemployed.

Whereas only one specific example of the invention has been describedhereinabove it will be understood that various changes may be madetherein without departing from the spirit of the invention or the scopeof the appended claims.

I claim:

1. in combination with an encased elongated drive motor having a driveshaft extension projecting axially therefrom,

coupling means on said drive shaft extension,

a pump assembly attached to said drive motor to be driven thereby,

said pump assembly including a lower adapter attached to said drivemotor, an elongate casing attached at its lower end to said loweradapter, a series of pump bowls stacked upon said lower adapter andsupported thereby, an upper adapter attached to the upper end of saidcasing whereby said bowls are sandwiched between said upper and loweradapters, a dilfuser assembly and an impeller disposed in each of saidbowls, each impeller having an axially elongate hub, and a pump shaftextending through said hubs for driving said impellers and having itslower end received in said coupling means,

said lower adapter having an upper gauge surface,

a sleeve surrounding said pump shaft and resting at its lower end uponsaid coupling means with its upper end at the height of said upper gaugesurface,

the lowermost bowl of said stack being engaged upon said lower adapterand having an upper gauge surface,

the hub of that impeller associated with said lowermost bowl being of anaxial extent such that its lower end, while resting upon said sleeve,positions its upper end at the level of said upper gauge surface of saidlowermost bowl,

all of said impeller hubs, all of said diffuser assemblies and all ofsaid bowls having identical axial extents and all of said bowls havingan upper gauge surface whereby any deviations of the heights of saidimpellers and said diffuser assemblies relative to the upper gaugesurface of an associated bowl may be detected to permit correction byshims and the like.

2. The combination according to claim 1 wherein a pair of bearingspiders are positioned in spaced relation to each other within saidstack of bowls and in spaced relation to said upper and lower adapters,and the pump assembly being devoid of any rigid bearing means at itsupper and lower ends to permit the opposite ends of said pump shaft todeflect for alignment purposes.

Ostenberg Aug. 16, 1921 Conant Mar. 31, 1931 (Qthcr references onfollowing page) UNITED STATES PATENTS 2,954,739 Meyers Oct. 30, 19343,025,800 Howard Jan. 9, 1945 Arutunoff Apr. 24, 1956 Buchi June 5, 19565 62273 123,153 Lung 10, Rice Dec. 17, 1957 10 Lung Oct. 4, 1960 Wolfeet a1. Mar. 20, 1962 FOREIGN PATENTS Austria Nov. 25, 1913 AustraliaJan. 17, 1947 Great Britain Apr. 17, 1957

1. IN COMBINATION WITH AN ENCASED ELONGATED DRIVE MOTOR HAVING A DRIVESHAFT EXTENSION PROJECTING AXIALLY THEREFROM, COUPLING MEANS ON SAIDDRIVE SHAFT EXTENSION, A PUMP ASSEMBLY ATTACHED TO SAID DRIVE MOTOR TOBE DRIVEN THEREBY, SAID PUMP ASSEMBLY INCLUDING A LOWER ADAPTER ATTACHEDTO SAID DRIVE MOTOR AN ELONGATE CASING ATTACHED AT ITS LOWER END TO SAIDLOWER ADAPTER, A SERIES OF PUMP BOWLS STACKED UPON SAID LOWER ADAPTERAND SUPPORTED THEREBY, AN UPPER ADAPTER ATTACHED TO THE UPPER END OFSAID CASING WHEREBY SAID BOWLS ARE SANDWICHED BETWEEN SAID UPPER ANDLOWER ADAPTERS, A DIFFUSER ASSEMBLY AND AN IMPELLER DISPOSED IN EACH OFSAID BOWLS, EACH IMPELLER HAVING AN AXIALLY ELONGATE HUB, AND A PUMPSHAFT EXTENDING THROUGH SAID HUBS FOR DRIVING SAID IMPELLERS AND HAVINGITS LOWER END RECEIVED IN SAID COUPLING MEANS, SAID LOWER ADAPTER HAVINGAN UPPER GAUGE SURFACE, A SLEEVE SURROUNDING SAID PUMP SHAFT AND RESTINGAT